This adds a general test to verify that a remote state backend returns
the expected error type when it cannot lock a state. It then extracts
the ID reported in the error, and attempts to unlock the state using
that ID, which simulated the force-unlock scenario. This is a separate
test, since not all backends have persistent locks that can be unlocked
later.
We also split out the backend test to be called individually as needed.
Go 1.9 adds this new function which, when called, marks the caller as
being a "helper function". Helper function stack frames are then skipped
when trying to find a line of test code to blame for a test failure, so
that the code in the main test function appears in the test failure output
rather than a line within the helper function itself.
This covers many -- but probaly not all -- of our test helpers across
various packages.
Remote state implementations may initialize a lineage when creating a
new named state (i.e. "workspace"). The tests were ignoring that initial
lineage to write a new state to the backend.
The backend state tests weren't properly checking for persistence.
Update the test to persist states and fetch them again from the backend,
checking that lineage is preserved.
This adds a "lock" config (default true) to allow users to optionally
disable state locking with Consul. This is necessary if the token given
doesn't have session permission and is necessary for backwards
compatibility.
Backends are a mechanism that allow abstracting the behavior of
Terraform CLI from the actual core. This allows us to slip in special
behavior such as state loading, remote operations, etc.
